91131616309 has 8 divisors (see below), whose sum is σ = 95877430488. Its totient is φ = 86505949440.

The previous prime is 91131616291. The next prime is 91131616313. The reversal of 91131616309 is 90361613119.

It can be written as a sum of positive squares in 4 ways, for example, as 21793140625 + 69338475684 = 147625^2 + 263322^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91131616309 - 2¹⁵ = 91131583541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91131616339) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30035272 + ... + 30038305.

It is an arithmetic number, because the mean of its divisors is an integer number (11984678811).

Almost surely, 2^91131616309 is an apocalyptic number.

It is an amenable number.

91131616309 is a deficient number, since it is larger than the sum of its proper divisors (4745814179).

91131616309 is a wasteful number, since it uses less digits than its factorization.

91131616309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60073655.

The product of its (nonzero) digits is 26244, while the sum is 40.

The spelling of 91131616309 in words is "ninety-one billion, one hundred thirty-one million, six hundred sixteen thousand, three hundred nine".